and maybe thousands more of the man called clark rockefeller. because investigators believe he was almost never whom he claimed to be. and in his rocket rise to the top of society, they think he committed murder. >> well, he's a man who built his life on fiction. >> reporter: mark seal wrote "the man in the rockefeller suit". the astonishing rise and spectacular fall of a serial imposter. >> he didn't just do this with one name or one persona. he did it repeatedliers time after time after time after time. in increasing grandiosity and increasingly intelligent, learned, successful circles. that's what makes him different. >> reporter: his story starts long ago in 1978 when under his real name, christian gehrhardt, a working class german teen he came to america and found the life he wanted on tv. >> good morning, mr. and mrs. howell. beautiful day, isn't it? >> ideal flying weather. >> if you remember the television show "gilligan's island". he started watching that. and apparently began to emulate the exsen tick east coast millionaire, thur ton h